Update actions/cache digest to 6682284 (#74)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/test-php.yml

@@ -34,7 +34,7 @@ jobs:
         uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
 
       - name: Cache Composer dependencies
-        uses: actions/cache@cdf6c1fa76f9f475f3d7449005a359c84ca0f306 # v5
+        uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5
         with:
           path: /tmp/composer-cache
           key: ${{ matrix.os }}-php-${{ matrix.php-versions }}-${{ matrix.deps }}-${{ hashFiles('**/composer.lock') }}